Passion fruit is a plant in the genus Passiflora, family Passifloraceae, known otherwise as kudamono tokeiso. The fruit is sweet and sour, and is eaten as a fruit, juiced for drinking, or added to foodstuff or beverages such as jellies and cakes to add flavor. Passion fruit seeds are hard, and removed from the fruit when juiced. Even if the seeds are consumed with the fruit, the outer skin of the seeds is hard and difficult to digest, and the seeds are therefore excreted intact.
Conventionally, passion fruit seeds have been discarded without utilization; however, the applicants of the present invention reported that passion fruit seed extract can be effectively utilized as an active component for inhibiting melanin production or as an active component for enhancing collagen production (Patent Citations 1 and 2). The applicants also reported that the active component in question is piceatannol, which is a polyphenol compound (Patent Citation 3).
With regards to scirpusin B, which is a dimer of piceatannol, it has been reported that the substance has anti-HIV activity (Non-Patent Citation 1), has superoxide anion removal activity (Non-Patent Citation 2), has α-amylase activity inhibitory activity (Non-Patent Citation 3), and has xanthine oxidase inhibitory activity (Non-Patent Citation 4).